U.S. patent number 4,838,774 [Application Number 07/119,398] was granted by the patent office on 1989-06-13 for apparatus for making a spun-filament fleece.
This patent grant is currently assigned to Reifenhauser GmbH & Co Maschinenfabrik. Invention is credited to Hermann Balk.
United States Patent |
4,838,774 |
Balk |
June 13, 1989 |
Apparatus for making a spun-filament fleece
Abstract
The apparatus for making a spun-filament fleece from a stretched
thermoplastic monofilament has a combined spinning unit made up of
separate spinning units each having a plurality of spinning nozzles
arranged in rows over a rectangular cross section, a blower shaft,
a stretching shaft and a wire screen conveyor for the finished
deposited fleece. The blower shaft is provided with air orifices
for admission of stretching air simultaneously acting as a cooler.
The stretching shaft has stretching shaft walls which are, if
necessary, movable or adjustable with an accelerating device with a
venturi nozzle like vertical cross section. At least two separate
spinning units with separate groups of spinning nozzles are located
above the blower shaft. At least one separating wall located
between individual spinning units divides the blower shaft into
separate portions for separate bands of monofilaments generated by
the separate groups of spinning nozzles. The separate spinning
units can be supplied with different thermoplastic materials from
different extruders.
Inventors: |
Balk; Hermann (Troisdorf,
DE) |
Assignee: |
Reifenhauser GmbH & Co
Maschinenfabrik (Troisdorf, DE)
|
Family
ID: |
6319149 |
Appl.
No.: |
07/119,398 |
Filed: |
November 10, 1987 |
Foreign Application Priority Data
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Jan 21, 1987 [DE] |
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3701531 |
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Current U.S.
Class: |
425/66;
264/176.1; 264/211.14; 264/237; 425/72.2 |
Current CPC
Class: |
D04H
3/16 (20130101); D01D 5/088 (20130101) |
Current International
Class: |
D04H
3/16 (20060101); D01D 005/12 () |
Field of
Search: |
;19/299,300
;28/185,240,241,273
;264/12,103,176.1,177.17,177.19,210.8,211.14,211.17,237,518,290.5,DIG.73,DIG.7
;425/66,72.1,72.2,80.1,81.1,82.1,140,141,172,83.1,462,464 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2049594 |
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Jan 1972 |
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DE |
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1950435 |
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Apr 1975 |
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DE |
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3406346 |
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Aug 1986 |
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DE |
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47-50003 |
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Dec 1972 |
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JP |
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Primary Examiner: Woo; Jay H.
Assistant Examiner: Bushey; C. Scott
Attorney, Agent or Firm: Dubno; Herbert
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application is related to the commonly owned concurrently
filed copending applications Ser. Nos. 07/119,141; 07/119,197; and
07/119,400 now U.S. Pat. Nos. 4,820,142; 4,812,112; and 4,820,459,
respectively.
Claims
I claim:
1. An apparatus for making a spun-filament fleece, comprising:
a pair of separate spinnerets each having a plurality of spinning
nozzles for emitting respective curtains of continuous
thermoplastic filaments downwardly;
means forming a cooling shaft below said spinnerets receiving said
curtains of continuous thermoplastic filaments, said cooling shaft
having walls respectively juxtaposed with outer sides of said
curtains and extending therealong;
a partition in said cooling shaft extending downwardly between said
curtains, separating said curtains in said cooling shaft and
juxtaposed with inner sides of said curtains;
nozzle means formed on said walls for directing jets of cooling air
into said shaft and inwardly along said curtains of thermoplastic
filaments opposite and along said partition;
a stretching shaft below said cooling shaft and formed with
stretching-shaft walls narrowing to define a venturi-line
air-accelerating stretching gap and thereafter widening downwardly
from said gap, whereby said curtains merge in said stretching shaft
and said thermoplastic filaments are stretched;
an air-permeable receiving conveyor displaceable below said
stretching shaft for receiving a fleece of said thermoplastic
filaments depositing from said curtains; and
an additional nozzle means formed on said partition and oriented to
direct respective jets of cooling air outwardly against each of
said curtains.
2. The apparatus defined in claim 1, further comprising a single
extruder connected to both of said spinnerets.
3. The apparatus defined in claim 1, further comprising a
respective extruder connected to each of said spinnerets.
4. An apparatus for making a spun-filament fleece, comprising:
a pair of separate spinnerets each having a plurality of spinning
nozzles for emitting respective curtains of continuous
thermoplastic filaments downwardly;
means forming a cooling shaft below said spinnerets receiving said
curtains of continuous thermoplastic filaments, said cooling shaft
having walls respectively juxtaposed with outer sides of said
curtains and extending therealong;
a partition in said cooling shaft extending downwardly between said
curtains, separating said curtains in said cooling shaft and
juxtapose with inner sides of said curtains;
nozzle means formed on said walls for directing jets of cooling air
into said shaft and inwardly against said curtains of thermoplastic
filaments opposite and along said partition;
a stretching shaft below said cooling shaft and formed with
stretching-shaft walls narrowing to define a venturi-like
air-accelerating stretching gap and thereafter widening downwardly
from said gap, whereby said curtains merge in said stretching shaft
to stretch said thermoplastic filaments, said stretching-shaft
walls being movable relative to one another to adjust a width of
said gap;
an air-permeable receiving conveyor displaceable below said
stretching shaft for receiving a fleece of said thermoplastic
filaments depositing from said curtains; and
an additional nozzle means formed on said partition and oriented to
direct respective jets of cooling air outwardly against each of
said curtains.
Description
FIELD OF THE INVENTION
My present invention relates to an apparatus for making a
spun-filament fleece and to the manufacture of a spun-filament
fleece from thermoplastic monofilament.
BACKGROUND OF THE INVENTION
An apparatus for making a spun-filament fleece from a stretched
thermoplastic monofilament made of a synthetic resin material can
include a spinning unit or spinneret including a plurality of
spinning nozzles arranged in rows in a rectangular pattern.
The thermoplastic, issuing as a band of monofilaments into a blower
shaft is exposed to a transverse blast of cooling air. The
filaments are then stretched in a stretching shaft by outflowing
air.
Then the stretched thermoplastic monofilaments are deposited as a
fleece on a continuously moving fleece-receiving conveyor or belt
beneath the stretching shaft. The conveyor may be a wire fabric
belt.
The blower shaft is provided with a plurality of air orifices for
admission of stretching air simultaneously serving as a cooling
means. The stretching shaft has a stretching shaft wall, if
necessary movable, with an accelerating device with a
venturi-nozzle like vertical cross section.
In the known apparatus for making a spun-filament fleece as
described in German Pat. Document No.35 03 818 the spinning nozzles
form a single spinning unitor spinneret. A single band of plastic
monofilaments issues from the spinning nozzles. This construction
leads to certain limitations. On the one hand the throughput per
spinning nozzle and thus for the entire apparatus can not be
arbitrarily increased. If an attempt is made to increase
throughput, a reduction in the quality of the finished fleece or
nonwoven mat results. Also the fleece or nonwoven mat cannot be
made from different thermoplastic materials or differently colored
materials.
OBJECTS OF THE INVENTION
It is an object of my invention to provide an improved apparatus
for making a spun-filament fleece which will obviate these
drawbacks.
It is another object of my invention to provide an improved
apparatus for making a spun-filament fleece which has a
substantially higher throughput than existing apparatus without
impairing the quality of the finished fleece.
It is also an object of my invention to provide an improved
apparatus for making a spun-filament fleece which is made from
different thermoplastic materials or different colored
materials.
SUMMARY OF THE INVENTION
These objects and others which will become more readily apparent
hereinafter are attained in accordance with my invention in an
apparatus for making a spun-filament fleece from a stretched
thermoplastic monofilament made of a thermoplastic material
comprising a spinning unit including a plurality of spinning
nozzles arranged in rows over a rectangular cross section, a blower
shaft, a stretching shaft and a wire cloth conveyor for the
spun-filament fleece. The blower shaft is provided with a plurality
of air orifices for admission of stretching air simultaneously
acting as a cooling means and the stretching shaft has, if
necessary, movable or adjustable stretching shaft walls with an
accelerating nozzle with a venturi-like vertical cross section.
According to my invention at least two parallel spinning members
(i.e. spinning beams) which each have a separate spinning unit or
spinneret including a separate plurality of spinning nozzles are
positioned above the blower shaft and at least one separating wall
extends at least over half the depth of the blower shaft and is
positioned between the spinning members or spinning units.
The separating wall can be a blower wall and have a plurality of
transversely blowing air orifices in both sides or both portions of
the blower shaft.
Both spinning units can be connected to one and the same
extruder.
It is also possible, however, in alternative embodiments of my
invention to connect each spinning unit or spinning nozzle to a
different extruder. Thus the fleece can be made from different
plastic materials or different colored materials. It should be
obvious that one can generalize the teachings of my invention both
in regard to process engineering and plant technology so that one
can not only process and make two different bands of thermoplastic
monofilaments but also three or more.
Among the advantages attained by my invention by comparison to the
earlier spun-filament mat-making apparatus is the following: a
substantially higher throughput can be obtained without impairing
the finished fleece quality.
Furthermore it is possible to make a fleece from different
thermoplastic materials and from materials which are colored
differently. It is also possible to change the physical parameters
so that different flow rates or different spinning nozzles are
used. It is understood that the thermoplastic stretched
monofilaments are endless filaments.
BRIEF DESCRIPTION OF THE DRAWING
The above and other objects, features and advantages of my
invention will become more readily apparent from the following
description, reference being made to the accompanying highly
diagrammatic drawing in which:
FIG. 1 is a vertical cross sectional view through an apparatus for
making a spun-filament fleece according to my invention;
FIG. 2 is a similar view of another embodiment of an apparatus for
making a spun-filament fleece according to my invention
corresponding to that of FIG. 1; and
FIG. 3 is yet another vertical section through an additional
embodiment of an apparatus for making a spun-filament fleece
according to my invention.
SPECIFIC DESCRIPTION
The apparatus shown in the drawing basically comprises a spinning
unit 1, 2 including a plurality of spinning nozzles 3, 4 arranged
in rows over a rectangular cross section, a blower shaft 5, a
stretching shaft 6 and a wire cloth conveyor 7 for the delivered
fleece with a device 8 for drawing or moving the process air.
The blower shaft 5 is provided with a plurality of air orifices 9
for admission of stretching air which simultaneously acts as a
cooling medium. The stretching shaft 6 has stretching shaft walls
10 which can be movable, with an accelerating device 11 which is
like a venturi nozzle in vertical cross section. The
fleece-receiving conveyor 7, which is a wire cloth conveyor in this
embodiment, as already mentioned, is located beneath the stretching
shaft 6.
Two parallel spinning beams 12, 13 each have a respective spinneret
I, 2 of the combined unit 1, 2.
Each separate spinneret 1, 2 or spinning beam 12, 13 has a separate
plurality of spinning nozzles 3, 4 located above the blower shaft 5
dispensing respective curtains of thermoplastic filaments.
A separating wall 14 which in this embodiment (FIG. 1) extends over
more than half the depth T of the blower shaft 5 is positioned
between the spinning members 12, 13.
In the embodiments according to FIGS. 1 and 3 the separating wall
14 is a closed separating wall without additional functions.
In the embodiment according to FIG. 2 the separating wall 14 is a
blower wall having a central air duct 19 with an air inlet 18 and
provides both portions 5a, 5b of the blower shaft 5 with
transversely blowing nozzle means in the form of air orifices 9 for
cooling air.
In the embodiments according to FIGS. 1 and 2 the apparatus is
connected to two extruders 15 so that the fleece can be made from
different plastic materials or from different colored plastic
material.
In the embodiment according to FIG. 3 the apparatus is connected to
a single extruder 15.
In all cases the separate spinnerets 1, 2 having the separate
pluralities of spinning nozzles 3, 4 can have different numbers of
nozzles and also differently shaped nozzles.
In continuous operation the thermoplastic material is fed to the
two separate spinnerets 1, 2 having the separate groups of spinning
nozzles 3, 4 arranged in rows.
Two thermoplastic bands of monofilaments 16, 17 issuing from the
separate spinnerets 1, 2 are exposed to cooling air separately in
separate portions 5a , 5b of the blower shaft 5 and both plastic
bands of monofilaments 16, 17 are jointly fed into a single
stretching shaft 6 and are jointly deposited on the wire cloth
conveyor 7 combined into a single finished spun-filament fleece or
nonwoven mat 20.
* * * * *